Sanders currently tops the MPP list with an ‘A’ rating. The organization cites his remarks at the first Democratic Debate in Las Vegas in early October, when the senator was asked how he would vote on a statewide initiative to legalize and regulation marijuana.

He responded to the debate moderator, “I suspect I would vote yes. And I would vote yes because I am seeing in this country too many lives being destroyed for non-violent offenses. We have a criminal justice system that lets CEOs on Wall Street walk away, and yet we are imprisoning or giving jail sentences to young people who are smoking marijuana.”

Paul’s ‘A-’ rates just behind Sanders, thanks to his consistent support of “states’ rights to establish their own marijuana policies.” The report card also cites the Kentucky senator’s sponsorship of the CARERS act, which would allow states to set their own agendas on medical marijuana regulation.

“Both of those candidates have gone out of their way to point out that federal marijuana laws are broken and need to be reformed,” said Dan Riffle, federal policy director at MPP.

A candidate’s stance on marijuana policy may prove increasingly important as more and more Americans shift towards supporting legalization. A recent Gallup Poll found that 58 percent of Americans believe marijuana should be legal across the country, up 7 points from last year. In 2000 only 30 percent of the country supported legalization.

But politicians have been slower to advocate support for legalization or decriminalization of the drug. Some, like Sanders, say they support legalization and decriminalizing cannabis as part of a broader push for criminal justice reform.

Others, like Democratic candidate and former Maryland Gov. Martin O’Malley, believe the drug should simply be re-scheduled so that it’s no longer considered a drug with no medical benefits—a move that could make it easier for scientists to study.

And some, like Republican Mike Huckabee, who received a ‘B-’ rating in the MPP report, are against marijuana’s use entirely but nevertheless believe that states should develop their own policies on the drug without the federal government’s interference.

“If you look at the other candidates in the field, Ted Cruz, Jeb Bush, Hillary Clinton—they’ve all said states ought to be laboratories of democracy and they ought to determine their own policies and this shouldn’t be a federal concern,” said Riffle.

That’s enough for Riffle and other marijuana advocates, who hope that if and when candidates with that mentality take office, “those folks working in those administrations would facilitate passage of legislation in Congress” to make legalization a states’ issue.

“We’re not talking about taxing and regulating marijuana federally but just resolving the tension between state and federal marijuana laws,” he said. “I think most likely the nominee for both parties will have the same positions—the positions that this is a state issue, let states determine their own laws.”